Method and apparatus for casting metal.



A. STANOWSKY.

METHOD AND APPARATUS FOR CASTING METAL.

APPLICATION FILED JAN-24,1918.

1,27 3,41 8. Patented July 23, 1918.

FIG.2.

19W l %g A 2 -2 7 I 5 FIGJ. I 1 4 A 26 31% 8 28 1& L I

ALEXANDER STAN OWSKY, 0F ROTTERDAM, NETHERLANDS.

METHOD AND APPARATUS FOR CASTING METAL.

Specification of Letters Patent.

Patented July 23, 1918.

Application filed January 24, 1918. Serial No. 213,552.

To all whom it may concern:

Be it known that I, ALEXANDER STANO'W- SKY, residing at Rotterdam, the Netherlands, have invented certain new and useful Improvements in Methods and Apparatus for Casting Metal, of which the following is a specification.

This invention relates to a method and to an apparatus for casting metal such as Is extensively used by dentists for casting gold plates for artificial teeth, but which may also be employed for other purposes. The

'said apparatus comprises a flask in which the model or pattern formed of wax or the like may be placed in a pad of refractory and absorbent material which in its original state is plastic but which hardens on being heated, the said model being in communication through a narrow passage with a crucible located within the muifle and preferably formed by a depression at the top of the pad. This pad,- after the attern is burned out constitutes the mold. ien the flask is heated and the model melted, the wax or the gases generated disperse through the refractory pad, whereby in the latter a cavity is left which exactly corresponds to the outline of the casting to be made. At the same time the required quantity of gold or other metal is brought to a molten state, after which the flask is closed and a gas under high ressure, for instance carbonic acid, is intro uced thereinto, by which the molten metal is pressed through the narrow passage into the cavity which thereby is entirely filled up.

Apparatus of this class as hitherto in use are rather expensive and not easily handled, as their operation depends upon a big cylinder containing the gas under high pressure or upon an air pump and the necessary connection pipes, which are liable to leakage and in many other respects cause considerable trouble. According to the present invention this disadvantageous feature is obviated in a simple manner by the gas under pressure being let into the flask from a capsule whose wall 'on being pressed against the lid of the flask is punctured by a piercer provided with a passage and placed in or on the flask, in such a manner, that an open connection between the capsule and the interior of the flask is obtained.

The annexed drawing illustrates some embodiments of an apparatus for carrying out the said method. In this drawing Figure 1 is an elevation, partly a section, of an apparatus embodying the invention,

Fig. 2 a section of the upper part of the flask and of its lid with a capsule, placed on same, whereas;

Figs. 3 and 4 illustrate sections of two ilidfi'erent forms of the piercer for use in the In Fig. 1, 1 is the flask, 2 the refractory and absorbent pad therein (forming the I mold), 3 is the model placed in the said pad,

old, placed in a depression of the pad.

a lever 6 which at 7 is pivoted to a support 8. A lever 9, which b means of a rod 10 and wing nut 11 is a apted to be fixed to the lid, is pivoted at 12 to the arm 13 of the lever 6, and has-for its purpose to forcibly press the capsule 14, which may be filled withliquid carbonic acid, on the lid 5, a rubber stuffing ring 15 serving for securing a tight connection.

According to Fig. 2 the lid 5 is provided on itstop with a collar 16, inclosing a chamber whose bottom 17 has a central aperture for the passage of the piercer 18, which is provided with. a shoulder 19. The piercer 18 is formed with a passage which constitutes the required connection between the space 20 in the covered flask (z'. e. the entire space within the assembled flask and lid), and the chamber inclosed by the collar 16 and the bottom wall 17. In the embodiment shown in Fig. 3 the said passage is simply formed by a longitudinal saw-notch 21 extending from the top to a small distance from the bottom'end through about half the thickness of the piercer. The piercer as shown in Fig. 4 is provided'with a longitudinal bore hole 22 which, after the piercer has been placed in the proper position, is in connection with the mufilc space 20 through a transverse passage 23.

. A baffle plate 24; is secured to the bottom end of the piercer 18 by means of a screw connection or in some other manner, a cer- 1 plate 24, may be varied considerably, so 55 tain space being left between theupper face of this plate and the bottom face of the wall 17, whereas the peripher of the plate 24 extends to quite near t e inner wall of the lid. V The operation of the apparatus is as follows After the model or pattern 'i'nclosed b the refractory pad in the flask is melte the wax absorbed, and the gold brought to a molten state, a ca sule 14 containing carbonic acid or the li e and closed at its bottom by a thin metal plate 25, is placed between the suitably formed lever 9 and the lid 5, after a rubber washer or stufling ring 15 has been arranged around the neck of the capsule. If now the lever 9 is forcibly pressed down, the ring 15 is gripped between the capsule 14 and the upper face of the collar 16, and the piercer 18 punctures the plate 25 of the ca sule, so' 'that the carbonic acid in the capsu e is free to flow through the passages 21, or 22 and 23, into the chamber formed between the bafile plate 24 and the bottom face of 17. From thischamber it flows around the edge of thebafiie plate 24 into the flask space 20 where it brings about the required pressure to force the gold through the 'assage 26 into the cavity formed in the pad? The excess of carbonic acid is blown off through a hole 27 in the bottom of the flask and through an opening 28 in the base plate.

It will thus be seen that the flask 1 and the lid 5, taken together form .a container,

. and whenthe capsule 14 is inplace, such capsule. forms ahermetic closure for such container. The bottom, or thin part 25 of said capsule initially forms the closure to the perforation in the lid 5, whereas, when the capsule 14 is pressed downwardly against the piercer 18, t is thin bottom of. the ca 1 sule is ierced and the as inthe capsu e enters the container. A ter the bottom of the capsule is pierced, the upper part ofthe capsule forms the closure'for the perforation in thelid (of course in combination with the packin ring 15). The be e plate 24 has for its object to prevent the carbonic acid flowing out of the capsule from-blowing away the molten gold centrally below it.

The structure and location of the 'bafiie as it is so located and constructed as to perform the function just stated. Said bame plate'can be secured to the piercer 18, as shown, or held in place in anyother suitable manner.-

What I claim as my invention is:

1. A metal-casing method of that type in which the molten metal is forced by gas underpressure into a mold located within a long diflusing the gas.

2. A metal-casting method of that type in which the molten metal is forced by gas under pressure into a mold located within a flask provided with a perforated lid, such method'comprising the successive steps ofclosing the perforation in the lid by means includm a capsule of gas under high pressure, an thereafter puncturing such capsule at that point thereof at which it initiall serves to form the closure of the said perf ration, whereby the contents of the capsule are admitted through the said perforation into the lid and flask and deflecting the high ressure gas current sufliciently to prevent t e same from directly striking the molten metal, whereby the pressure is applied only indirectly on such molten metal.

'3. In combination, in a metal casting device, a flask contaimng a mold, a perforated lid for such flask, an outwardly extendin collar surrounding the perforation in suc lid, such collar forming a chamber, a piercer located within such chamber and being rovided with a longitudinal passage, the ottom of said piercer being located in the perforation in said lid, a bafile plate located within the inclosure formed by the flask and its lid, and being situated between the said perforation and the mold,- and adapted to deflect the such inclosure, in such a way that the stron gas current does not strike the molten meta located on the mold.

gas under pressure flowing into 4, In a metal casting device, the combination of a flask contalnlng a mold, a lid for said flask, such lid being provided with a hole, a piercer carried by said lid in proxmity to said hole, a compressed gas capsule adapted to completely cover said hole and to form a pressure-tight closure therefor, means for pressing such ca sule against such p1ercer, wh1le maintainlng the said capsule m'positlon to form a pressure ti ht. closure forsuch hole, a passage for al owing the compressed gas from said capsule to enter the said flask, and meansfor deflecting and current, whereby the gas pressure only, and not the current, comes lnto direct contact with the metal in the mold.

5. In the art of casting metal in a mold located w1th-1n a pressure-tight container, the mprovement which comprisespositioning a capsule containing gas under high pressure, where its interior, when the Wall of such capsule is punctured, will be in communication with the interior of such container containing such mold and containing molten metal in communication with such mold, and then puncturing the wall of such capsule, whereby its high pressure gas contents are allowed to flow into such container, to increase the gas pressure existing 10 therein.

In testimony whereof I have affixed my signature in presence of two witnesses.

ALEXANDER STANOWSKY.

Witnesses PLANTE FEBERE, H. VEIHGEL. 

